86 Ranger problem starting

I have a 2.9 4x4 86 ranger. I have started having problems getting it started. The starter turns but when it fires it will disengage and just spin. My first thought is the solindoid, but I am not sure.

It is getting gas.

Ideas?

if you replace the starter drive in your starter it will work, again, as it's suppose to... you can buy a starter repair kit, at checker auto for $12.99, that includes the starter drive, brushes, bushings, and thrust washers, which after putting these all parts in, will make your starter as good as a new one...

Wouldn't be simpler to add a couple more bucks and just buy a new or rebuilt starter?